13.9.4 HTML preamble and postamble

The HTML exporter has delineations for preamble and postamble. The default value for org-html-preamble is t, which makes the HTML exporter insert the preamble. See the variable org-html-preamble-format for the format string.

Set org-html-preamble to a string to override the default format string. If set to a function, the HTML exporter expects the function to return a string upon execution. The HTML exporter inserts this string in the preamble. The HTML exporter does not insert a preamble if org-html-preamble is set nil.

The above also applies to org-html-postamble and org-html-postamble-format. In addition, org-html-postamble can be set to auto (its default value), which makes the HTML exporter build a postamble from looking up author’s name, email address, creator’s name, and date.